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A query processing method for integrated access to multiple databases

  • Itaru Nishizawa
  • Atsuhiro Takasu
  • Jun Adachi
Advanced Database and Information System Methods 3
Part of the Lecture Notes in Computer Science book series (LNCS, volume 1134)

Abstract

Multiple autonomous databases within a network system often contain similar information although their schemata are heterogeneous. This paper considers such heterogeneity and proposes a new method for achieving integrated access to multiple databases having similar schema. The method is based on the construction of a “virtual database (VDB)” by making use of null values and “virtual functional dependency (VFD),” which are formed over physically distributed component databases and applied to the query processing. We could obtain additional information relevant to the query and proved that this information is logically valid. When the VFD formed over a VDB is acyclic among the nodes that the query refers to, sound and complete answers can be efficiently calculated. We developed and implemented a bibliographic information retrieval system employing the schema integration method described herein such that integrated access is obtained for bibliographic information written in BibTEX.

Keywords

Information Retrieval Query Processing Server Side Bibliographic Database Information Retrieval System 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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References

  1. 1.
    Lim, E., Srivastava, J., Prebhakar, S. and Richardson, J.: Entity Identification in Database Integration. IEEE Proceedings of the Ninth International Conference. (1993) 294–301Google Scholar
  2. 2.
    Fagin, R.: Horn Clauses and Database Dependencies. J. ACM. 29 (1982) 952–985CrossRefGoogle Scholar
  3. 3.
    Reiter, R.: Towards a Logical Reconstruction of Relational Database Theory. On Conceptual Modelling: Perspectives from Artificial Intelligence, Databases and Programming Languages. (1984) 191–233Google Scholar
  4. 4.
    Litwin, W., Mark, L. and Roussopoulos, N.: Interoperability of Multiple Autonomous Databases. ACM Comput. Surv. 22 (1990) 267–293CrossRefGoogle Scholar
  5. 5.
    Armstrong, W. W.: Dependency Structures of Data Base Relationships. Information Processing. (1974) 580–583Google Scholar
  6. 6.
    Lloyd, J. W.: Foundations of Logic Programming — Second, Extended Edition. (1987)Google Scholar
  7. 7.
    Nishizawa, I., Takasu, A. and Adachi, J.: Query processing method for multiple databases having different set of attributes, The Transactions of the Institute of Electronics, Information and Communication Engineers. 79-DI (1996) 18–27Google Scholar
  8. 8.
    Reiter, R.: A Sound and Sometimes Complete Query Evaluation Algorithm for Relational Databases with Null Values. J. ACM. 33 (1986) 349–370CrossRefGoogle Scholar
  9. 9.
    Ullman, J. D.: Principles of Database and Knowledge-Base Systems Volume I and II. Computer Science Press. (1988)Google Scholar
  10. 10.
    Patashnik, O.: BibTEXing. Documentation for general BibTEXing users in BibTEXing package. (1988)Google Scholar

Copyright information

© Springer-Verlag Berlin Heidelberg 1996

Authors and Affiliations

  • Itaru Nishizawa
    • 1
  • Atsuhiro Takasu
    • 2
  • Jun Adachi
    • 2
  1. 1.Department of Electrical EngineeringThe University of TokyoTokyoJapan
  2. 2.R&D DepartmentNational Center for Science Information SystemsTokyoJapan

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